Only one tower of ours has recorded relative humidity and ipack voltage at the same time (other towers have sensors occupying all channels). Unfortunately, the scenario that I described in the previous post does not apply to the RH5 on that tower, so I cannot offer more clues.
Let's say the iPack battery has ran out of power because of cloudy sky, and thus the RH5 readings go to zero. Is the RH5 supposed to be able to function properly again once the battery is recharged and the voltage goes back to 12V?

We have quite a few RH5 or RH5X at various field locations. One problem we have ran into is that the range of the recorded relative humidity will gradually change, typically the range will be 30%-95% during the 1/2 year of deployment (which matches with records from nearby weather station), then the range will become 0-100% afterwards (while the nearby weather station is still recording 30%-95% relative humidity), and eventually the RH5/RH5X will give completely invalid readings.
- what is the estimated service life of the RH5/RH5X?
- is RH5/RH5X supposed to be re-calibrated in the field at a certain time interval?
Thank you for your time and attention.

We post-calibrated some #40Cs. In some cases, the difference in slopes and offsets before and after ~2 years of field deployment appears to be quite significant. For example, the slope and offset of one #40C were 0.76 and 0.29 at the beginning, and changed to 0.771 and 0.47 after field deployment.
- Any advice on how to incorporate the post-calibration scale factors into wind assessment?
- Can NRG share any analysis on comparison between pre- and post- field deployment scale factors?
Thank you for your attention and help.